Abstract:

A double clutch transmission with two clutches whose input sides are
connected to a drive shaft and whose output sides are each connected to
one of two transmission input shafts positioned coaxial with respect to
one another. At least two countershafts provided and support toothed
idler gearwheels while the two transmission input shafts support toothed
fixed gearwheels such that it is possible to shift at least a plurality
of power shift forward gears and/or at least one reverse gear. Five gear
planes are provided so that at least one winding path gear is shiftable
when at least one coupling device, assigned to the output gear, is
disengaged.

Claims:

1-21. (canceled)

22. A double clutch transmission comprising:first and second clutches (K1,
K2) each having an input side connected to a drive shaft (w_an) and an
output side connected to one of a first and a second transmission input
shaft (w_k1, w_k2) coaxially arranged with respect to one another;at
least first and second countershafts (w_v1, w_v2) upon which toothed
idler gearwheels (8, 9, 10, 11, 12, 13, 14, 15) are rotationally
supported;the first and the second transmission input shafts (w_k1, w_k2)
supporting fixed gearwheels (1, 2, 3, 4, 5), and the fixed gearwheels (1,
2, 3, 4, 5) meshing with at least one of the idler gearwheels (8, 9, 10,
11, 12, 13, 14, 15);a plurality of coupling devices (A, B, C, D, E, F, G,
H) for coupling an idler gearwheel (8, 9, 10, 11, 12, 13, 14, 15) with
one of the first and the second countershafts (w_v1, w_v2) in a
rotationally fixed manner;a first output gear (17) being provided on the
first countershaft (w_v1) and a second output gear (18) being provided on
the second countershaft (w_v2), and each of the first and the second
output gears (17, 18) being coupled to gearing of an output shaft (w_ab)
so that at least several power shiftable forward gears (1, 2, 3, 4, 5, 6,
7) and at least one reverse gear (R1, R2, R3, R4) being shiftable;wherein
the double clutch transmission has five gear planes (8-1, 8-12, 9-2,
9-13, 3-13, 10-3, 10-14, 4-14, 11-15) and at least two of the five gear
planes are dual gear planes (8-12, 9-13, 10-14, 11-15), each of the dual
gear planes (8-12, 9-13, 10-14, 11-15) comprises an idler gearwheel (8,
9, 10, 11, 12, 13, 14, 15) of each of the first and the second
countershafts (w_v1, w_v2) and a fixed gear (1, 2, 4, 5) of one of the
first and the second transmission input shafts (w_k1, w_k2), at least one
idler gearwheel (8, 9, 10, 11, 12, 13, 14, 15) in each of the dual gear
planes (8-12, 9-13, 10-14, 11-15) is utilized for at least two gears such
that at least one winding path gear is shiftable when upon disengagement
of one of a first output coupling device (S_ab1) associated with the
first output gear (17) and a second output coupling device (S_ab2)
associated with the second output gear (18).

23. The double clutch transmission according to claim 22, wherein upon
disengagement of the first coupling device (S_ab1) on the first
countershaft (w_v1), at least one of a first forward gear (G1), an eighth
forward gear (G8), a reverse gear (R1, R2, R3, R4), a crawler gear (C1,
C3, C5) and an overdrive gear (O3, O4, O5, O6, O7, O8) is shiftable as a
winding path gear.

24. The double clutch transmission according to claim 22, wherein upon
disengagement of the second output coupling device (S_ab2) on the second
countershaft (w_v2), at least one of an eighth forward gear (G8), a
reverse gear (R1, R2, R3, R4), a crawler gear (C1, C2, C4) and an
overdrive gear (O2, O3, O5) is shiftable as a winding path gear.

25. The double clutch transmission according to claim 22, wherein the
first countershaft (w_v1) supports at least one shift element (I), and
upon activation of the at least one shift element (I) on the first
countershaft (w_v1), an idler gear (9) of a second sub-transmission is
connectable to an idler gear (10) of a first sub-transmission so that at
least one of a first forward gear (G1), a reverse gear (R1), a crawler
gear (C1, C2) and an overdrive gear (O1, O2, O4, O5) is shiftable as a
winding path gear.

26. The double clutch transmission according to claim 22, wherein the
second countershaft (w_v2) supports at least one shift element (K), and
upon activation of the at least one shift element (K) on the second
countershaft (w_v2) an idler gear (13) of a second sub-transmission is
connectable to an idler gear (14) of a first sub-transmission so that at
least one of a first forward gear (G1), a reverse gear (R2), a crawler
gear (C3) and an overdrive gear (O1, O2, O3) is shiftable as a winding
path gear.

27. The double clutch transmission according to claim 22, wherein the
double clutch transmission comprises two dual gear planes and three
single gear planes, each of a first gear plane (8-1), a second gear plane
(9-2) and a third gear plane (3-13) is a single gear plane and comprises
a fixed gear (1, 2, 3) of the second transmission input shaft (w_k2) of a
second sub-transmission, and a fourth gear plane (10-14) and a fifth gear
plane (11-15) are dual gear planes and each comprise a fixed gear (4, 5)
of the first transmission input shaft (w_k1) of a first sub-transmission.

28. The double clutch transmission according to claim 22, wherein the
double clutch transmission comprises three dual gear planes and two
single gear planes, a first gear plane (8-12) is a dual gear plane, a
second gear plane (9-2) is a single gear plane, and a third gear plane
(3-13) is a single gear plane, each of the first, the second and the
third gear planes comprise a fixed gear (1, 2, 3) of the second
transmission input shaft (w_k2) of a second sub-transmission, and a
fourth gear plane (10-14) is a dual gear plane, and a fifth gear plane
(11-15) is a dual gear plane, and each of the fourth and the fifth gear
planes comprise a fixed gear (4, 5) of the first transmission input shaft
(w_k1) of a first sub-transmission.

29. The double clutch transmission according to claim 22, wherein the
double clutch transmission comprises three dual gear planes and two
single gear planes, a first gear plane (8-12) and a second gear plane
(9-13) are both dual gear planes and comprises a fixed gear (1, 2) of the
second transmission input shaft (w_k2) of a second sub-transmission, and
a third gear plane (10-3) and a fourth gear plane (4-14) are each a
single gear plane, and a fifth gear plane (11-15) is a dual gear plane,
and the third, the fourth, the fifth gear planes each comprise a fixed
gears (3, 4, 5) of the first transmission input shaft (w_k1) of a first
sub-transmission.

30. The double clutch transmission according to claim 22, whereina first
forward gear (G1) is shiftable as a winding path fear via activation of
activation of the first clutch (K1), a second coupling device (B), a
fourth coupling device (D) and a fifth coupling device (E) and
disengagement of the first output coupling device (S_ab1);a second
forward gear (G2) is shiftable via activation of the second clutch (K2)
and the fifth coupling device (E);a third forward gear (G3) is shiftable
via activation of the first clutch (K1) and the fourth coupling device
(D);a fourth forward gear (G4) is shiftable via activation of the second
clutch (K2) and the second coupling device (B);a fifth forward gear (G5)
is shiftable via activation of the first clutch (K1) and a seventh
coupling device (G);a sixth forward gear (G6) is shiftable via activation
of the second clutch (K2) and a sixth coupling device (F);a seventh
forward gear (G7) is shiftable via activation of the first clutch (K1)
and a third coupling device (C);an eighth forward gear (G8) is shiftable
as a winding path gear via activation of the second clutch (K2), the
fourth coupling device (D), the sixth coupling device (F) and the eighth
coupling device (H) and by disengagement of the second output coupling
device (S_ab2);a first reverse gear (R1) is shiftable as a winding path
gear via activation of the second clutch (K2), a first coupling device
(A), the third coupling device (C) and an eighth coupling device (H) and
by disengagement of first output coupling device (S_ab1);a second reverse
gear (R2) is shiftable as a winding path gear via activation of the first
clutch (K1), the first coupling device (A), the fourth coupling device
(D) and the fifth coupling device (E) and by disengagement of the first
output coupling device (S_ab1); anda third reverse gear (R3) is shiftable
as a winding path gear via activation of the first clutch (K1), the first
coupling device (A), the sixth coupling device (F) and the eighth
coupling device (H) and by disengagement of the second output coupling
device (S_ab2).

31. The double clutch transmission according to claim 22, whereina first
forward gear (G1) is shiftable as a winding path gear via activation of
the first clutch (K1), a second coupling device (B), a fourth coupling
device (D) and a fifth coupling device (E) and by disengagement of the
first output coupling device (S_ab1);a second forward gear (G2) is
shiftable via activation of the second clutch (K2) and the fifth coupling
device (E);a third forward gear (G3) is shiftable via activation of the
first clutch (K1) and the fourth coupling device (D);a fourth forward
gear (G4) is shiftable via activation of the second clutch (K2) and the
second coupling device (B);a fifth forward gear (G5) is shiftable via
activation of the first clutch (K1) and a seventh coupling device (G);a
sixth forward gear (G6) is shiftable via activation of the second clutch
(K2) and a sixth coupling device (F);a seventh forward gear (G7) is
shiftable via activation of the first clutch (K1) and a third coupling
device (C);an eighth forward gear (G8) is shiftable as a winding path
gear via activation of the second clutch (K2), the third coupling device
(C), the fifth coupling device (E) and an eighth coupling device (H) and
by disengagement of the second output coupling device (S_ab2);a first
reverse gear (R1) is shiftable as a winding path gear via activation of
the second clutch (K2), a first coupling device (A), the third coupling
device (C) and the eighth coupling device (H) and by disengagement of the
first output coupling device (S_ab1);a second reverse gear (R2) is
shiftable as a winding path gear via activation of the first clutch (K1),
the first coupling device (A), the fourth coupling device (D) and the
fifth coupling device (E) and by disengagement of the first output
coupling device (S_ab1);a third reverse gear (R3) is shiftable as a
winding path gear via activation of the first clutch (K1), the first
coupling device (A), the sixth coupling device (F) and the eighth
coupling device (H) and by disengagement of the second output coupling
device (S_ab2).

32. The double clutch transmission according to claim 30, whereina first
crawler gear (C1) is shiftable as a winding path gear via activation of
the second clutch (K2), the fourth coupling device (D) and a first shift
element (I);a crawler gear (C2) is shiftable as a winding path gear via
activation of the second clutch (K2), the fourth coupling device (D), the
fifth coupling device (E) and the seventh coupling device (G) and by
disengagement of the second output coupling device (S_ab2);a first
overdrive gear (O1) is shiftable as a winding path gear via activation of
the second clutch (K2), the third coupling device (C) and a second shift
element (K);a second overdrive gear (O2) is shiftable as a winding path
gear via activation of the first clutch (K1), the sixth coupling device
(F) and the first shift element (I);a third overdrive gear (O3) is
shiftable as a winding path gear via activation of the second clutch
(K2), the third coupling device (C), the sixth coupling device (F) and
the seventh coupling device (G), and by disengagement of the second
output coupling device (S_ab2);a fourth overdrive gear (O4) is shiftable
as a winding path gear via activation of the first clutch (K1), the
second coupling device (B), the third coupling device (C) and the sixth
coupling device (F) and by disengagement of the first output coupling
device (S_ab1).

33. The double clutch transmission according to claim 22, whereina first
forward gear (G1) is shiftable via activation of the first clutch (K1)
and a third coupling device (C);a second forward gear (G2) is shiftable
via activation of the second clutch (K2) and a first coupling device
(A);a third forward gear (G3) is shiftable via activation of the first
clutch (K1) and a fourth coupling device (D);a fourth forward gear (G4)
is shiftable via activation of the second clutch (K2) and a second
coupling device (B);a fifth forward gear (G5) is shiftable via activation
of the first clutch (K1) and a seventh coupling device (G);a sixth
forward gear (G6) is shiftable via activation of the second clutch (K2)
and a sixth coupling device (F);a seventh forward gear (G7) is shiftable
via activation of the first clutch (K1) and a eighth coupling device
(H);an eighth forward gear (G8) is shiftable as a winding path gear via
activation of the second clutch (K2), the first coupling device (A), the
third coupling device (C) and the eighth coupling device (H) and by
disengagement of the first output coupling device (S_ab1);a first reverse
gear (R1) is shiftable as a winding path gear via activation of the
second clutch (K2), the third coupling device (C), a fifth coupling
device (E) and the seventh coupling device (G) and by disengagement of
the second output coupling device (S_ab2);a second reverse gear (R2) is
shiftable as a winding path gear via activation of the second clutch
(K2), the third coupling device (C), a fifth coupling device (E) and the
eighth coupling device (H) and by disengagement of the second output
coupling device (S_ab2);a third reverse gear (R3) is shiftable as a
winding path gear via activation of the second clutch (K2), the fourth
coupling device (D), the fifth coupling device (E) and the eighth
coupling device (H) and by disengagement of the second output coupling
device (S_ab2); anda fourth reverse gear (R4) is shiftable as a winding
path gear via activation of the first clutch (K1), first coupling device
(A), the fifth coupling device (E) and the seventh coupling device (G)
and by disengagement of the second output coupling device (S_ab2).

34. The double clutch transmission according to claim 33, whereina first
crawler gear (C1) is shiftable as a winding path gear via activation of
the second clutch (K2), the third coupling device (C), the sixth coupling
device (F) and the eighth coupling device (H) and by disengagement of the
second output coupling device (S_ab2);a second crawler gear (C2) is
shiftable as a winding path gear via activation of the first clutch (K1),
the first coupling device (A) and a first shift element (I);a third
crawler gear (C3) is shiftable as a winding path gear via activation of
the first clutch (K1), the first coupling device (A) and a second shift
element (K);a fourth crawler gear (C4) is shiftable as a winding path
gear via activation of the first clutch (K1), the first coupling device
(A), the sixth coupling device (F) and the seventh coupling device (G)
and by disengagement of the second output coupling device (S_ab2);a first
overdrive gear (O1) is shiftable as a winding path gear via activation of
the second clutch (K2), the seventh coupling device (G) and the first
shift element (I);a second overdrive gear (O2) is shiftable as a winding
path gear via activation of the second clutch (K2), the eighth coupling
device (H) and the first shift element (I);a third overdrive gear (O3) is
shiftable as a winding path gear via activation of the second clutch
(K2), the eighth coupling device (H) and the second shift element (K);a
fourth overdrive gear (O4) is shiftable as a winding path gear via
activation of the second clutch (K2), the second coupling device (B), the
fourth coupling device (D) and the eighth coupling device (H), and by
disengagement of the first output coupling device (S_ab1); anda fifth
overdrive gear (O5) is shiftable as a winding path gear via activation of
the second clutch (K2), the second coupling device (B), the third
coupling device (C) and the eighth coupling device (H) and by
disengagement of the first output coupling device (S_ab1).

35. The double clutch transmission according to claim 22, whereina first
forward gear (G1) is shiftable as a winding path gear via activation of
the first clutch (K1), a first coupling device (A) and a first shift
element (I);a second forward gear (G2) is shiftable via activation of the
second clutch (K2) and the first coupling device (A);a third forward gear
(G3) is shiftable via activation of the first clutch (K1) and a third
coupling device (C);a fourth forward gear (G4) is shiftable via
activation of the second clutch (K2) and a second coupling device (B);a
fifth forward gear (G5) is shiftable via activation of the first clutch
(K1) and a seventh coupling device (G);a sixth forward gear (G6) is
shiftable via activation of the second clutch (K2) and a sixth coupling
device (F);a seventh forward gear (G7) is shiftable via activation of the
first clutch (K1) and a fourth coupling device (D);an eighth forward gear
(G8) is shiftable as a winding path gear via activation of the first
clutch (K1), the first coupling device (A), the third coupling device (C)
and the sixth coupling device (F) and by disengagement of the first
output coupling device (S_ab1);a first reverse gear (R1) is shiftable as
a winding path gear via activation of the second clutch (K2), the third
coupling device (C), a fifth coupling device (E) and an eighth coupling
device (H) and by disengagement of the second output coupling device
(S_ab2);a second reverse gear (R2) is shiftable as a winding path gear
via activation of the second clutch (K2), the fourth coupling device (D),
the fifth coupling device (E) and the eighth coupling device (H) and by
disengagement of the second output coupling device (S_ab2); anda third
reverse gear (R3) is shiftable as a winding path gear via activation of
the second clutch (K2), the third coupling device (C), the sixth coupling
device (F) and the eighth coupling device (H) and by disengagement of the
second output coupling device (S_ab2).

36. The double clutch transmission according to claim 35, wherein a
crawler gear (C1) is shiftable as a winding path gear via activation of
the second clutch (K2), the first coupling device (A), the fourth
coupling device (D) and the seventh coupling device (G) and by
disengagement of the first output coupling device (S_ab1);a first
overdrive gear (O1) is shiftable as a winding path gear via activation of
the second clutch (K2), the fourth coupling device (D) and the first
shift element (I);a second overdrive gear (O2) is shiftable as a winding
path gear via activation of the second clutch (K2), the fourth coupling
device (D) and a second shift element (K);a third overdrive gear (O3) is
shiftable as a winding path gear via activation of the first clutch (K1),
the first coupling device (A), the fourth coupling device (D) and the
sixth coupling device (F) and by disengagement of the first output
coupling device (S_ab1);a fourth overdrive gear (O4) is shiftable as a
winding path gear via activation of the first clutch (K1), the second
coupling device (B), the fourth coupling device (D) and the sixth
coupling device (F) and by disengagement of the first output coupling
device (S_ab1);a fifth overdrive gear (O5) is shiftable as a winding path
gear via activation of the second clutch (K2), the fourth coupling device
(D), the sixth coupling device (F) and the seventh coupling device (G)
and by disengagement of the second output coupling device (S_ab2).

37. The double clutch transmission according to claim 22, whereina first
forward gear (G1) is shiftable as a winding path gear via activation of
the first clutch (K1), a fifth coupling device (E) and a first shift
element (I);a second forward gear (G2) is shiftable via activation of the
second clutch (K2) and the fifth coupling device (E);a third forward gear
(G3) is shiftable via activation of the first clutch (K1) and a third
coupling device (C);a fourth forward gear (G4) is shiftable via
activation of the second clutch (K2) and a second coupling device (B);a
fifth forward gear (G5) is shiftable via activation of the first clutch
(K1) and an eighth coupling device (H);a sixth forward gear (G6) is
shiftable via activation of the second clutch (K2) and a sixth coupling
device (F);a seventh forward gear (G7) is shiftable via activation of the
first clutch (K1) and a fourth coupling device (D);an eighth forward gear
(G8) is shiftable as a winding path gear via activation of the second
clutch (K2), the fourth coupling device (D), the fifth coupling device
(E) and the seventh coupling device (G) and by disengagement of the
second output coupling device (S_ab2);a first reverse gear (R1) is
shiftable as a winding path gear via activation of the second clutch
(K2), a first coupling device (A), the fourth coupling device (D) and the
seventh coupling device (G) and by disengagement of the first output
coupling device (S_ab1);a second reverse gear (R2) is shiftable as a
winding path gear via activation of the first clutch (K1), the first
coupling device (A) and a second shift element (K);a third reverse gear
(R3) is shiftable as a winding path gear via activation of the first
clutch (K1), the first coupling device (A), the third coupling device (C)
and the fifth coupling device (E) and by disengagement of the first
output coupling device (S_ab1); anda fourth reverse gear (R4) is
shiftable as a winding path gear via activation of the first clutch (K1),
the first coupling device (A), the sixth coupling device (F) and the
seventh coupling device (G) and by disengagement of the second output
coupling device (S_ab2).

38. The double clutch transmission according to claim 37, whereina crawler
gear (C1) is shiftable as a winding path gear via activation of the
second clutch (K2), the third coupling device (C), the fifth coupling
device (E) and the eighth coupling device (H) and by disengagement of the
second output coupling device (S_ab2);a first overdrive gear (O1) is
shiftable as a winding path gear via activation of the second clutch
(K2), the fourth coupling device (D) and the first shift element (I);a
second overdrive gear (O2) is shiftable as a winding path gear via
activation of the second clutch (K2), the fourth coupling device (D), the
sixth coupling device (F) and the eighth coupling device (H) and by
disengagement of the second output coupling device (S_ab2);a third
overdrive gear (O3) is shiftable as a winding path gear via activation of
the first clutch (K1), the second coupling device (B), the fourth
coupling device (D) and the sixth coupling device (F) and by
disengagement of the first output coupling device (S_ab1).

39. The double clutch transmission according to claim 22, whereina first
forward gear (G1) is shiftable as a winding path gear via activation of
the first clutch (K1), a second coupling device (B) and a second shift
element (K);a second forward gear (G2) is shiftable via activation of the
second clutch (K2) and the second coupling device (B);a third forward
gear (G3) is shiftable via activation of the first clutch (K1) and a
seventh coupling device (G);a fourth forward gear (G4) is shiftable via
activation of the second clutch (K2) and a sixth coupling device (F);a
fifth forward gear (G5) is shiftable via activation of the first clutch
(K1) and a fourth coupling device (D);a sixth forward gear (G6) is
shiftable via activation of the second clutch (K2) and a fifth coupling
device (E);a seventh forward gear (G7) is shiftable via activation of the
first clutch (K1) and a third coupling device (C);an eighth forward gear
(G8) is shiftable as a winding path gear via activation of the first
clutch (K1), a first coupling device (A), the third coupling device (C)
and the sixth coupling device (F) and by disengagement of the first
output coupling device (S_ab1);a first reverse gear (R1) is shiftable as
a winding path gear via activation of the second clutch (K2), the fourth
coupling device (D), the sixth coupling device (F) and the eighth
coupling device (H) and by disengagement of the second output coupling
device (S_ab2).

40. The double clutch transmission according to claim 39, whereina first
crawler gear (C1) is shiftable as a winding path gear via activation of
the second clutch (K2), the fourth coupling device (D) and a first shift
element (I);a second crawler gear (C2) is shiftable as a winding path
gear via activation of the second clutch (K2), the seventh coupling
device (G) and the first shift element (I);a third crawler gear (C3) is
shiftable as a winding path gear via activation of the second clutch
(K2), the second coupling device (B), the fourth coupling device (D) and
the seventh coupling device (G) and by disengagement of the first output
coupling device (S_ab1);a fourth crawler gear (C4) is shiftable as a
winding path gear via activation of the first clutch (K1), the second
coupling device (B), the fifth coupling device (E) and the seventh
coupling device (G) and by disengagement of the second output coupling
device (S_ab2);a fifth crawler gear (C5) is shiftable as a winding path
gear via activation of the second clutch (K2), the second coupling device
(B), the third coupling device (C) and the seventh coupling device (G)
and by disengagement of the first output coupling device (S_ab1);a first
overdrive gear (O1) is shiftable as a winding path gear via activation of
the second clutch (K2), the third coupling device (C) and the second
shift element (K);a second overdrive gear (O2) is shiftable as a winding
path gear via activation of the second clutch (K2), the third coupling
device (C), the fifth coupling device (E) and the seventh coupling device
(G) and by disengagement of the second output coupling device (S_ab2);a
third overdrive gear (O3) is shiftable as a winding path gear via
activation of the second clutch (K2), the fourth coupling device (D), the
fifth coupling device (E) and the seventh coupling device (G) and by
disengagement of the second output coupling device (S_ab2);a fourth
overdrive gear (O4) is shiftable as a winding path gear via activation of
the first clutch (K1), the fifth coupling device (E) and the first shift
element (I);a fifth overdrive gear (O5) is shiftable as a winding path
gear via activation of the first clutch (K1), the sixth coupling device
(F) and the first shift element (I);a sixth overdrive gear (O6) is
shiftable as a winding path gear via activation of the first clutch (K1),
the second coupling device (B), the fourth coupling device (D) and the
fifth coupling device (E) and by disengagement of the first output
coupling device (S_ab1);a seventh overdrive gear (O7) is shiftable as a
winding path gear via activation of the first clutch (K1), the second
coupling device (B), the third coupling device (C) and the fifth coupling
device (E) and by disengagement of the first output coupling device
(S_ab1); andan eighth overdrive gear (O8) is shiftable as a winding path
gear via activation of the first clutch (K1), the second coupling device
(B), the third coupling device (C) and the sixth coupling device (F) and
by disengagement of the first output coupling device (S_ab1).

41. The double clutch transmission according to claim 22, whereina first
forward gear (G1) is shiftable as a winding path gear via activation of
the first clutch (K1), a fifth coupling device (E) and a second shift
element (K);a second forward gear (G2) is shiftable via activation of the
second clutch (K2) and a fifth coupling device (E);a third forward gear
(G3) is shiftable via activation of the first clutch (K1) and a seventh
coupling device (G);a fourth forward gear (G4) is shiftable via
activation of the second clutch (K2) and a sixth coupling device (F);a
fifth forward gear (G5) is shiftable via activation of the first clutch
(K1) and a fourth coupling device (D);a sixth forward gear (G6) is
shiftable via activation of the second clutch (K2) and a first coupling
device (A);a seventh forward gear (G7) is shiftable via activation of the
first clutch (K1) and a third coupling device (C);an eighth forward gear
(G8) is shiftable as a winding path gear via activation of the second
clutch (K2), the third coupling device (C), the fifth coupling device (E)
and an eighth coupling device (H) and by disengagement of the second
output coupling device (S_ab2);a first reverse gear (R1) is shiftable as
a winding path gear via activation of the first clutch (K1), the fifth
coupling device (E) and a first shift element (I);a second reverse gear
(R2) is shiftable as a winding path gear via activation of the first
clutch (K1), a second coupling device (B), the fourth coupling device (D)
and the fifth coupling device (E) and by disengagement of the first
output coupling device (S_ab1);a third reverse gear (R3) is shiftable as
a winding path gear via activation of the first clutch (K1), the second
coupling device (B), the fourth coupling device (D) and the sixth
coupling device (F) and by disengagement of the first output coupling
device (S_ab1); anda fourth reverse gear (R4) is shiftable as a winding
path gear via activation of the first clutch (K1), the second coupling
device (B), the third coupling device (C) and the fifth coupling device
(E) and by disengagement of the first output coupling device (S_ab1).

42. The double clutch transmission according to claim 41, wherein an
overdrive gear (O1) is shiftable as a winding path gear via activation of
the second clutch (K2), the third coupling device (C) and the second
shift element (K).

[0003]A six-speed or seven-speed double clutch transmission is known from
published patent DE 103 05 241 A1. The double clutch transmission
comprises two clutches, each of which is connected on its input side to
the drive shaft and on its output side to one of the two transmission
input shafts. The two transmission input shafts are placed coaxially
relative to each other. Furthermore, two countershafts are situated
axially parallel to the two transmission input shafts, with their idler
gears engaging the fixed gears of the transmission input shafts.
Moreover, coupling devices are held on the countershafts so that they are
axially movable and rotationally fixed, in order to be able to shift the
respective toothed gearwheels. The chosen transmission ratio is
transmitted to a differential through the output gears. In order to
realize the desired transmission ratio stages with the known double
clutch transmission, a large number of gear planes are necessary, so that
the construction space required for installation is not insignificant.

[0004]Furthermore, a spur-gear multi-speed transmission is known from
published patent DE 38 22 330 A1. The spur-gear multi-speed transmission
comprises a double clutch which is shiftable under load, one part of
which is connected to a driveshaft, and the other part of which is
connected to a hollow driveshaft that is rotatably supported on the
driveshaft. For certain transmission ratios, the driveshaft can be
coupled with the hollow driveshaft by means of a shift element.

[0005]From published patent DE 10 2004 001 961 A1 a power-shift
transmission with two clutches is known, each of which is assigned to a
subtransmission. The transmission input shafts of the two
subtransmissions are placed coaxially to each other, and are engaged with
idler gears of the countershafts via assigned fixed gears. The respective
idler gears of the countershafts can be connected in a rotationally fixed
manner with the respective countershaft by means of assigned shift
elements. From this published patent an eight-speed transmission is
known, in which an additional shift element is provided for coupling the
two transmission input shafts to realize an additional transmission ratio
stage. Even the seven-speed transmission in this form requires at least
six gear planes in the two subtransmissions, in order to be able to
realize the transmission ratio stages. This results in an undesirable
lengthening of the construction length in the axial direction, so that
the possibility of installation in a vehicle is significantly limited.

[0006]Furthermore, from published patent DE 10 2005 028 532 A1 an
additional power-shift transmission is known, which includes two input
shafts and only one countershaft. For example, an eight-speed
transmission in this form requires more than seven gear planes in order
to be able to realize the transmission ratio stages, including in
particular the reverse gear transmission ratios. This results in an
undesirable lengthening of the construction length in the axial
direction.

SUMMARY OF THE INVENTION

[0007]The object of the present invention is to propose a double clutch
transmission of the species described at the beginning, wherein a
plurality of power-shiftable transmission ratio stages are realized as
economically as possible and with the fewest possible parts while
requiring little construction space.

[0008]Accordingly, a construction-space-optimized double clutch
transmission with two clutches is proposed, whose input sides are
connected to a drive shaft, and whose output sides are each connected to
one of two transmission input shafts which are situated coaxially to each
other. The double clutch transmission comprises at least two
countershafts, on which toothed gearwheels designed as idler gears are
rotatably carried, there being toothed gearwheels designed as fixed
gears, at least some of which are engaged with the idler gears, supported
in a rotationally fixed manner on the two transmission input shafts. Also
provided are a plurality of coupling devices for connecting an idler gear
to a countershaft in a rotationally fixed manner. The double clutch
transmission according to the invention has an output gear or constant
pinion on each of the countershafts, each of which is coupled with
gearing of a drive shaft in order to connect the respective countershaft
with the output drive, making a plurality of power-shiftable gears
feasible.

[0009]According to the invention, the proposed double clutch transmission
preferably comprises only five gear planes, with which at least seven
power-shiftable gears are realized with little construction space
required. For example, one way in which the maximum of five gear planes
can be formed is by at least two dual gear planes, wherein in each dual
gear plane one idler gear of the first and second countershafts each is
assigned to a fixed gear of one of the transmission input shafts and at
least one idler gear is used for at least two gear speeds, so that at
least one winding path gear is shiftable when there is at least one
coupling device that is assigned to one of the output gears and is
disengaged.

[0010]It is also possible to use single gear planes besides the dual gear
planes, where in each single gear plane an idler gear of the
countershafts is assigned to a fixed gear of one of the transmission
input shafts. Other configurations are also possible.

[0011]Because of the possible multiple uses of idler gears, it is possible
with the proposed double clutch transmission to realize a maximum number
of gear ratios with the fewest possible gear planes, with the first seven
forward gears preferably being power-shiftable with sequential design.

[0012]To optimize the stepping in the double clutch transmission proposed
according to the invention, it is also possible for example to replace a
dual gear plane with two single gear planes, by replacing one fixed gear
with two fixed gears. That makes it possible to achieve especially
harmonic, progressive gear stepping. It is also possible to replace two
single gear planes with one dual gear plane.

[0013]The proposed double clutch transmission can preferably be designed
as an 8-speed transmission with at least seven power-shiftable gear
steps. Because of the short construction compared to known transmission
arrangements, the double clutch transmission according to the invention
is especially suited for a front transverse design in a vehicle. Other
types of configurations are also possible, however, depending on the type
and construction space situation of the particular vehicle in question.

[0014]Preferably, in the proposed double clutch transmission the first
and/or eighth forward gears can be winding path gears. In addition, a
reverse gear and/or other gears, for example crawler gears or overdrive
gears, can also be designed as winding-path gears, and may possibly also
be power-shiftable. For example, the first power-shiftable forward gear
and the highest gear may be winding-path gears. Besides the two coupling
devices provided as winding path gear shift elements on the constant
pinions, additional shift elements can also be placed on the first and/or
on the second countershaft to realize additional winding path gears. Thus
both constant pinions are connected with the assigned countershaft in a
shiftable manner. Preferably, only five gear planes will be realized in
the proposed double clutch transmission, with at least two dual gear
planes and at least two single gear planes being used.

[0015]For example, depending on the design, it is possible for four
shiftable idler gears to be assigned to the first countershaft, each of
them engaging with fixed gears of the assigned transmission input shafts.
On the second countershaft, preferably three or four shiftable idler
gears can be realized, each of which meshes with fixed gears of the
assigned transmission input shaft.

[0016]If the last or next-to-last gear step is shifted higher than the one
before it, especially high output torque or drive power can be made
available when a downshift is requested by the driver.

[0017]Advantageously, in the double clutch transmission according to the
invention a maximum of five shift points are needed on a countershaft. In
total, however, a maximum of nine shift points on the two countershafts
together can be sufficient to realize the proposed gear steps. Additional
shift points are also possible.

[0018]According to the invention, provision can be made for the idler gear
of the second subtransmission to be connected with the idler gear of the
first subtransmission via the at least one additional shift element on
the first and/or second countershaft, so that at least one winding path
gear can be shifted by means of the shift element.

[0019]With the double clutch transmission according to the invention it is
thus possible, with the coupling devices on the output gears disengaged,
by means of the at least one switch element, to realize winding path
gears, in which toothed gearwheels of both subtransmissions are coupled
with each other in order to thereby realize a flow of power through both
subtransmissions. The particular shift element utilized serves in this
case to couple two idler gears, and thereby brings the transmission input
shafts into dependency on each other.

[0020]In the double clutch transmission, the arrangement of the shift
elements for coupling two particular idler gears can be varied so that
the shift elements do not necessarily have to be placed between the idler
gears that are to be coupled. Accordingly, other arrangement positions of
the particular shift element are also conceivable, in order for example
to optimize linking to an actuator system.

[0021]In the double clutch transmission it is possible according to one
embodiment for two dual gear planes and three single gear planes to be
provided, there being a first gear plane, a second gear plane and a third
gear plane assigned to the fixed gears of the second transmission input
shaft of the second subtransmission, each of them as a single gear plane,
and there being a fourth gear plane and a fifth gear plane assigned to
the fixed gears of the first transmission input shaft, each of them as a
dual gear plane.

[0022]In another embodiment of the invention, it is also possible for
three dual gear planes and two single gear planes to be provided in the
proposed double clutch transmission. For example, a first gear plane as a
dual gear plane, a second gear plane as a single gear plane and a third
gear plane as a single gear plane can be assigned to the fixed gears of
the second transmission input shaft of the second subtransmission, and a
fourth gear plane and a fifth gear plane can be assigned to the fixed
gears of the first transmission input shaft of the first subtransmission,
each of them as a dual gear plane.

[0023]Alternatively, a first gear plane and a second gear plane as single
gear planes can also be assigned to the fixed gears of the second
transmission input shaft of the second subtransmission, each of them as a
dual gear plane, and a third gear plane and a fourth gear plane can be
assigned to the fixed gears of the first transmission input shaft of the
first subtransmission, each of them as a single gear plane, as well as a
fifth gear plane as a dual gear plane.

[0024]In order to provide the necessary reversal of rotation to realize
reverse gears in the double clutch transmission according to the
invention, it is possible to use at least one intermediate gear or the
like, which is situated for example on an intermediate shaft. It is also
possible for one of the idler gears of a countershaft to serve as the
intermediate gear wheel for at least one reverse gear. No additional
intermediate shaft is then necessary for the reverse gear, since one of
the idler gears meshes both with a fixed gear and with another shiftable
idler gear of the other countershaft. Thus the necessary intermediate
gear wheel for the reverse gear is positioned on a countershaft as a
shiftable idler gear, and also serves to realize at least one additional
forward gear. The intermediate gear can also be designed as a stepped
gear, independent of whether it is placed on the countershaft or on an
additional intermediate shaft. It is also possible for the intermediate
gear to not be placed on one of the already existing countershafts, but
to be provided on another separate shaft, for example a third
countershaft.

[0025]In order to obtain the desired transmission ratio steps, the double
clutch transmission according to the invention may also include the
provision that at least one bidirectionally operative coupling device or
the like is situated on each countershaft. The provided coupling devices
can each connect an assigned idler gear with the countershaft in a
rotationally fixed manner in the activated or engaged state, depending on
the direction of operation. In addition, a unidirectionally operating
coupling device or the like can also be provided on at least one of the
countershafts. The coupling devices used can be for example
hydraulically, pneumatically, electrically or mechanically operated
clutches, or also form locking claw clutches, as well as any type of
synchronization device that provides a rotationally fixed connection
between an idler gear and a countershaft. It is possible for a
bidirectionally operative coupling device to be replaced by two
unidirectionally operative coupling devices, or vice versa.

[0026]It is conceivable that the indicated positioning options for the
toothed gearwheels may be varied, and also that the number of toothed
gearwheels and the number of coupling devices may be changed, in order to
realize still additional power-shiftable or non-power-shiftable gears, as
well as to save construction space and parts in the proposed double
clutch transmission. In particular, fixed gears of dual gear planes can
be divided into two fixed gears for two single gear planes. That makes it
possible to improve step changes. In addition, it is possible to exchange
the countershafts. It is also possible for the subtransmissions to be
exchanged i.e., to be mirrored around a vertical axis. In doing so, the
hollow shaft and solid shaft are exchanged. This makes it possible to
place the smallest gearwheel on the solid shaft, in order to further
optimize utilization of the available construction space. In addition,
neighboring gear planes can be exchanged, for example, to optimize shaft
flexing and/or to link a shift actuating system optimally. Moreover, the
particular placement position of the coupling devices at the gear plane
can be varied. Furthermore, the direction of action of the coupling
devices can also be changed.

[0027]The gear numberings used here were defined freely. It is also
possible to add a crawler or creeper gear and/or an overdrive or fast
gear, in order to improve the off-road properties or the acceleration
behavior of a vehicle. Furthermore, it is possible to omit a first gear,
for example, in order to better optimize the step changes overall. The
gear numbering varies logically when these measures are used.

[0028]Independent of the particular variant embodiments of the double
clutch transmission, the drive shaft and the output shaft may preferably
also not be situated coaxially to each other; this realizes an especially
space-saving arrangement. For example, the shafts, which are thus
positioned spatially one behind the other, may also be offset slightly
relative to each other. With this arrangement, a direct gear with a
transmission ratio of one is realizable by means of tooth engagement, and
can be advantageously shifted to the sixth through ninth gears relatively
freely. Other possible arrangements of the drive shaft and output shaft
are also conceivable.

[0029]Preferably, the proposed double clutch transmission is equipped with
an integrated output stage. The output stage can include, as the output
gear, a fixed gear on the output shaft, which meshes both with a first
output gear as a shiftable constant pinion of the first countershaft and
also with a second output gear as a shiftable constant pinion of the
second countershaft. Thus both output gears are designed as shiftable
gearwheels. To shift the particular output gear, a coupling device may be
assigned, which in its disengaged state releases the connection between
the assigned countershaft and the output gear, in order to shift winding
path gears.

[0030]Advantageously, the lower forward gears and the reverse gears can be
actuated via a start-up clutch or shifting clutch, in order to thereby
concentrate higher loads on this clutch so that the second clutch can be
designed for smaller construction space and at lower cost. In particular,
the gear planes in the proposed double clutch transmission can be
situated so that the vehicle can be set in motion either by means of the
inner transmission input shaft or the outer transmission input shaft, and
thus by means of whichever clutch is better suited in the particular
case; this is also possible with a concentrically arranged, radially
nested construction of the double clutch. To that end, the gear planes
may be correspondingly arranged mirror-symmetrically, or may be
exchanged.

[0031]Independent of the particular variant embodiment, in the double
clutch transmission the provided gear planes for example may be
exchanged.

BRIEF DESCRIPTION OF THE DRAWINGS

[0032]The present invention will be explained in greater detail below on
the basis of the drawing. The figures show the following:

[0033]FIG. 1 a schematic view of a 1st variant embodiment of an
eight-speed double clutch transmission according to the invention;

[0034]FIG. 2 a shift pattern of the 1st variant embodiment according to
FIG. 1;

[0035]FIG. 3 a schematic view of a 2nd variant embodiment of the
eight-speed double clutch transmission according to the invention;

[0036]FIG. 4 a shift pattern of the 2nd variant embodiment according to
FIG. 3;

[0037]FIG. 5 a schematic view of a 3rd variant embodiment of the
eight-speed double clutch transmission according to the invention;

[0038]FIG. 6 a shift pattern of the 3rd variant embodiment according to
FIG. 5;

[0039]FIG. 7 a schematic view of a 4th variant embodiment of the
eight-speed double clutch transmission according to the invention;

[0040]FIG. 8 a shift pattern of the 4th variant embodiment according to
FIG. 7;

[0041]FIG. 9 a schematic view of a 5th variant embodiment of the
eight-speed double clutch transmission according to the invention;

[0042]FIG. 10 a shift pattern of the 5th variant embodiment according to
FIG. 9;

[0043]FIG. 11 a schematic view of a 6th variant embodiment of the
eight-speed double clutch transmission according to the invention;

[0044]FIG. 12 a shift pattern of the 6th variant embodiment according to
FIG. 11;

[0045]FIG. 13 a schematic view of a 7th variant embodiment of the
eight-speed double clutch transmission according to the invention; and

[0046]FIG. 14 a shift pattern of the 7th variant embodiment according to
FIG. 13.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0047]FIGS. 1, 3, 5, 7, 9, 11 and 13 each show a possible variant
embodiment of an eight-speed double clutch transmission. The respective
shift patterns for the different variant embodiments are depicted in
tabular form in FIGS. 2, 4, 6, 8, 10, 12 and 14.

[0048]The eight-speed double clutch transmission comprises two clutches
K1, K2, whose input sides are connected to a driveshaft w_an and whose
output sides are each respectively connected to one of two transmission
input shafts w_k1, w_k2 which are positioned coaxially to each other. In
addition, a torsion vibration damper 19 can be placed on the driveshaft
w_an. Furthermore, two countershafts w_v1, w_v2 are provided, on which
toothed gear wheels in the form of idler gears 8, 9, 10, 11, 12, 13, 14,
15 are rotatably supported. Placed on the two transmission input shafts
w_k1, w_k2 are rotationally fixed toothed gearwheels in the form of fixed
gears 1, 2, 3, 4, 5 at least some of which are meshed with the idler
gears 8, 9, 10, 11, 12, 13, 14, 15.

[0049]In order to be able to connect the idler gears 8, 9, 10, 11, 12, 13,
14, 15 with the respective countershaft w_v1, w_v2, a plurality of
activatable coupling devices A, B, C, D, E, F, G, H are provided on the
countershafts w_v1, w_v2. Furthermore, situated on the two countershafts
w_v1, w_v2 as constant pinions are output gears 17, 18 each of which
couples gearing of a fixed gear 16 of an output shaft w_ab, with
corresponding output stages i_ab_1, i_ab_2 assigned to the output gears
17, 18.

[0050]Besides coupling devices A, B, C, D, E, F, G, H which in the
activated state realize a rotationally fixed connection between a toothed
gearwheel and the assigned countershaft w_v1, w_v2, on each of first and
second countershafts w_v1, w_v2 a winding path gear coupling device
S_ab1, S_ab2 is assigned to output stage i_ab1, i_ab2. When coupling
device S_ab1 or S_ab2 is disengaged, the rotationally fixed connection
between the output gear 17 or 18 and the first countershaft w_v1 or
second countershaft w_v2 can be released. In the double clutch
transmission it is possible if necessary to provide at least one winding
path gear shift element I or K to connect two toothed gearwheels of a
countershaft w_v1, w_v2 in a rotationally fixed manner, so that at least
one winding path gear may also be realized through the activated shift
elements I, K.

[0051]According to the invention, only five gear planes 8-1, 8-12, 9-2,
9-13, 3-13, 10-3, 10-14, 4-14, 11-15 are provided in the double clutch
transmission, there being at least two dual gear planes 8-12, 9-13,
10-14, 11-15 provided in each variant embodiment, so that winding path
gears are shiftable at least when coupling devices S_ab1 and S_ab2 are
disengaged, and additionally if necessary by means of at least one of the
activated shift elements I, K. A claw or the like may be used as the
shift elements I, K for connecting two gearwheels or the like.

[0052]Shift element K, if present, is positioned on second countershaft
w_v2, in order to connect idler gear 13 with idler gear 14 when shift
element K is activated. Shift element I, if present, is provided on first
countershaft w_v1, in order to connect idler gear 9 with idler gear 10
when shift element I is activated.

[0053]In the 1st, 2nd and 5th variant embodiments according to FIGS. 1, 3
and 9, in the first gear plane 8-12 as a dual gear plane, fixed gear 1 of
the second transmission input shaft w_k2 meshes both with idler gear 12
of the second countershaft w_v2 and also with an intermediate gear ZR on
an intermediate shaft w_zw for reversing the rotation for the reverse
gear transmission ratios, with intermediate gear ZR also meshing with
idler gear 8 of the first countershaft w_v1. In the second gear plane
9-2, as a single gear plane, fixed gear 2 of the second transmission
input shaft w_k2 meshes with idler gear 9 of the first countershaft w_v1.
In the third gear plane 3-13, as a single gear plane, fixed gear 3 of the
second transmission input shaft w_k2 meshes with idler gear 13 of the
second countershaft w_v2. Furthermore, in the fourth gear plane 10-14 as
a dual gear plane, fixed gear 4 of the first transmission input shaft
w_k1 meshes both with idler gear 10 of the first countershaft w_v1 and
also with idler gear 14 of the second countershaft w_v2. In the fifth
gear plane 11-15, as a dual gear plane, fixed gear 5 of the first
transmission input shaft w_k1 meshes both with idler gear 11 of the first
countershaft w_v1 and also with idler gear 15 of the second countershaft
w_v2. The only difference in the 3rd variant embodiment according to FIG.
5 is that in the first gear plane 8-12, as a dual gear plane, fixed gear
1 of the second transmission input shaft w_k2 meshes directly with idler
gear 8 of the first transmission shaft w_v1 and is coupled indirectly
through an intermediate gear ZR with idler gear 12 of the second
countershaft w_v2 for reversing the rotation.

[0054]In the 4th variant embodiment according to FIG. 7, in the first gear
plane 8-1 as a single gear plane, fixed gear 1 of the second transmission
input shaft w_k2 meshes with idler gear 8 of the first transmission shaft
w_v1. In the second gear plane 9-2, as a single gear plane, fixed gear 2
of the second transmission input shaft w_k2 meshes with idler gear 9 of
the first countershaft w_v1. In the third gear plane 3-13, as a single
gear plane, fixed gear 3 of the second transmission input shaft w_k2
meshes with idler gear 13 of the second countershaft w_v2. In addition,
in the fourth gear plane 10-14 as a dual gear plane, fixed gear 4 of the
first transmission input shaft w_k1 meshes both with idler gear 10 of the
first countershaft w_v1 and also with idler gear 14 of the second
countershaft w_v2. Finally, in the fifth gear plane 11-15 as a dual gear
plane, fixed gear 5 meshes both with idler gear 11 of the first
countershaft w_v1 and also with intermediate gear ZR on the intermediate
shaft w_zw to reverse the rotation for the reverse gear transmission
ratios, with intermediate gear ZR also meshing with idler gear 15 of the
second countershaft w_v2.

[0055]In the 6th and 7th variant embodiments according to FIGS. 11 and 13,
in the first gear plane 8-12 as a dual gear plane, fixed gear 1 of the
second transmission input shaft w_k2 meshes both with idler gear 8 of the
first countershaft w_v1 and also with idler gear 12 of the second
countershaft w_v2. In the 6th variant embodiment, in the second gear
plane 9-13, as a dual gear plane, fixed gear 2 of the second transmission
input shaft w_k2 meshes both with idler gear 9 of the first countershaft
w_v1 and also with idler gear 13 of the second countershaft w_v2. In
contrast, in the 7th variant embodiment, fixed gear 2 meshes both with
idler gear 13 of the second countershaft w_v2 and also with intermediate
gear ZR for reversing the rotation for the reverse transmission ratios,
with intermediate gear ZR also meshing with idler gear 9 of the first
countershaft w_v1. In the third gear plane 10-3, as a single gear plane,
in both the 6th and the 7th variant embodiments fixed gear 3 of the
second transmission input shaft w_k2 meshes with idler gear 10 of the
first countershaft w_v1. In the fifth gear plane 4-14, as a single gear
plane, fixed gear 4 of the first transmission input shaft w_k1 meshes
with idler gear 14 of the second countershaft w_v2. In the 6th variant
embodiment, in the fifth gear plane 11-15, as a dual gear plane, fixed
gear 5 of the first transmission input shaft w_k1 meshes both with idler
gear 11 of the first countershaft w_v1 and also with intermediate gear ZR
for reversing the rotation for the reverse gear transmission ratios, with
intermediate gear ZR also meshing with idler gear 15 of the second
countershaft w_v2. On the other hand, in the 7th variant embodiment,
fixed gear 5 meshes both with idler gear 11 of the first countershaft
w_v1 and also with idler gear 15 of the second countershaft w_v2.

[0056]In all of the variant embodiments according to FIGS. 1 through 14,
in each case two bidirectionally operative coupling device A-B and C-D
are provided on the first countershaft w_v1, the coupling devices A-B,
C-D being arranged so that the activated coupling device A connects idler
gear 8, the activated coupling device B connects idler gear 9, the
activated coupling device C connects idler gear 10 and the activated
coupling device D connects idler gear 11, in each case to first
countershaft w_v1 in a rotationally fixed manner.

[0057]In the 1st, 2nd, 3rd, 5th, 6th and 7th variant embodiments according
to FIGS. 1, 3, 5, 9, 11 and 13, in each case there are two doubly
operative coupling devices E-F and G-H assigned to the second
countershaft w_v2, the coupling devices E-F and G-H being arranged so
that the activated coupling device E connects idler gear 12, the
activated coupling device F connects idler gear 13, the activated
coupling device G connects idler gear 14 and the activated coupling
device H connects idler gear 15, in each case to second countershaft w_v2
in a rotationally fixed manner.

[0058]In the 4th variant embodiment according to FIG. 7, a
unidirectionally operative coupling device F and a bidirectionally
operative coupling device G-H are assigned to the second countershaft
w_v2, the coupling devices F and G-H being arranged so that the activated
coupling device F connects idler gear 13, the activated coupling device G
connects idler gear 14 and activated coupling device H connects idler
gear 15, in each case to the second countershaft w_v2 in a rotationally
fixed manner.

[0059]Independent of the particular variant embodiments, an integrated
output stage with the output gear 17 and with the output gear 18 is
provided in the double clutch transmission according to the invention.
Output gear 17 and output gear 18 each mesh with a fixed gear 16 of
output shaft w_ab. Preferably, shiftable connections are realized between
output gears 17, 18 and the assigned countershafts w_v1, w_v2 by the
shiftable coupling devices S_ab1, S_ab2.

[0060]Another result in the double clutch transmission according to the
invention is that at least the forward gears G1 through G7 may be
designed to be power shiftable. Depending on the variant embodiment, the
eighth forward gear G8, reverse gears, crawler gears and/or overdrive
gears can be designed to be power shiftable as winding path gears.
Details for each variant embodiment will be evident from the shift
patterns described below.

[0061]The table depicted in FIG. 2 shows an example of a shift pattern for
the 1st variant embodiment of the eight-speed double clutch transmission
according to FIG. 1.

[0062]It is evident from the shift pattern that the first forward gear G1
is shiftable by means of the first clutch K1, the activated coupling
device B, the activated coupling device D and the activated coupling
device E, and also as a winding path gear when coupling device S_ab1 is
disengaged, that the second forward gear G2 is shiftable by means of the
second clutch K2 and the activated coupling device E, that the third
forward gear G3 is shiftable by means of the first clutch K1 and the
activated coupling device D, that the fourth forward gear G4 is shiftable
by means of the second clutch K2 and the activated coupling device B,
that the fifth forward gear G5 is shiftable by means of the first clutch
K1 and the activated coupling device G, that the sixth forward gear G6 is
shiftable by means of the second clutch K2 and the activated coupling
device F, and that the seventh forward gear G7 is shiftable by means of
the first clutch K1 and the activated coupling device C. Thus, at least
the first seven forward gears can be designed to be power shiftable.
Furthermore, the eighth forward gear G8 can be shifted by means of the
second clutch K2, the activated coupling device D, the activated coupling
device F and the activated coupling device H, and also as a winding path
gear when coupling device S_ab2 is disengaged.

[0063]Furthermore, a reverse gear R1 for example can be shifted by means
of the second clutch K2, the activated coupling device A, the activated
coupling device C and the activated coupling device H and also as a
winding path gear when coupling device S_ab1 is disengaged, a reverse
gear R2 can be shifted by means of the first clutch K1, the activated
coupling device A, the activated coupling device D and the activated
coupling device E and also as a winding path gear when coupling device
S_ab1 is disengaged, a reverse gear R3 can be shifted by means of the
first clutch K1, the activated coupling device A, the activated coupling
device F and the activated coupling device H and also as a winding path
gear when coupling device S_ab2 is disengaged.

[0064]The table depicted in FIG. 4 shows an example of a shift pattern for
the 2nd variant embodiment of the eight-speed double clutch transmission
according to FIG. 3.

[0065]It is evident from the shift pattern that the first forward gear G1
is shiftable by means of the first clutch K1, the activated coupling
device B, the activated coupling device D and the activated coupling
device E, and also as a winding path gear when coupling device S_ab1 is
disengaged, that the second forward gear G2 is shiftable by means of the
second clutch K2 and the activated coupling device E, that the third
forward gear G3 is shiftable by means of the first clutch K1 and the
activated coupling device D, that the fourth forward gear G4 is shiftable
by means of the second clutch K2 and the activated coupling device B,
that the fifth forward gear G5 is shiftable by means of the first clutch
K1 and the activated coupling device G, that the sixth forward gear G6 is
shiftable by means of the second clutch K2 and the activated coupling
device F, that the seventh forward gear G7 is shiftable by means of the
first clutch K1 and the activated coupling device C, and that the eighth
forward gear G8 is shiftable by means of the second clutch K2, the
activated coupling device C, the activated coupling device E and the
activated coupling device H, and also as a winding path gear when
coupling device S_ab2 is disengaged. Thus, at least the first eight
forward gears can be designed to be power shiftable.

[0066]Furthermore, in the 4th variant embodiment it is possible for a
reverse gear R1 to be shifted by means of the second clutch K2, the
activated coupling device A, the activated coupling device C and the
activated coupling device H and also as a winding path gear when coupling
device S_ab1 is disengaged, a reverse gear R2 to be shifted by means of
the first clutch K1, the activated coupling device A, the activated
coupling device D, the activated coupling device E and also as a winding
path gear when coupling device S_ab1 is disengaged, a reverse gear R3 to
be shifted by means of the first clutch K1, the activated coupling device
A, the activated coupling device F and the activated coupling device H,
and also as a winding path gear when coupling device S_ab2 is disengaged.

[0067]Furthermore, the tables depicted in FIGS. 2 and 4 show shift
patterns respectively for the 1st and 2nd variant embodiments according
to FIGS. 1 and 3.

[0068]Accordingly, in the 1st and 2nd variant embodiments for example a
crawler gear C1 can be shifted by means of the second clutch K2 and the
activated coupling device D, and also as a winding path gear when shift
element I is activated, a crawler gear C2 can be shifted by means of the
second clutch K2, the activated coupling device D, the activated coupling
device E and the activated coupling device G, and also as a winding path
gear when coupling device S_ab2 is disengaged, an overdrive gear O1 can
be shifted by means of the second clutch K2 and the activated coupling
device C, and also as a winding path gear by means of the activated shift
element K, an overdrive gear O2 can be shifted by means of the first
clutch K1 and the activated coupling device F, and also as a winding path
gear by means of the activated shift element I, an overdrive gear O3 can
be shifted by means of the second clutch K2, the activated coupling
device C, the activated coupling device F and the activated coupling
device G, and also as a winding path gear when coupling device S_ab2 is
disengaged, an overdrive gear O4 can be shifted by means of the first
clutch K1, the activated coupling device B, the activated coupling device
C and the activated coupling device F, and also as a winding path gear
when coupling device S_ab1 is disengaged.

[0069]The table depicted in FIG. 6 shows an example of a shift pattern for
the 3rd variant embodiment of the eight-speed double clutch transmission
according to FIG. 5.

[0070]It is evident from the shift pattern that the first forward gear G1
is shiftable by means of the first clutch K1 and the activated coupling
device C, that the second forward gear G2 is shiftable by means of the
second clutch K2 and the activated coupling device A, that the third
forward gear G3 is shiftable by means of the first clutch K1 and the
activated coupling device D, that the fourth forward gear G4 is shiftable
by means of the second clutch K2 and the activated coupling device B,
that the fifth forward gear G5 is shiftable by means of the first clutch
K1 and the activated coupling device G, that the sixth forward gear G6 is
shiftable by means of the second clutch K2 and the activated coupling
device F, that the seventh forward gear G7 is shiftable by means of the
first clutch K1 and the activated coupling device H, and that the eighth
forward gear G8 is shiftable by means of the second clutch K2, the
activated coupling device A, the activated coupling device C and the
activated coupling device H, and also as a winding path gear when
coupling device S_ab1 is disengaged. Thus, at least the first eight
forward gears can be designed to be power shiftable.

[0071]Furthermore, a reverse gear R1 can be shifted by means of the second
clutch K2, the activated coupling device C, the activated coupling device
E and the activated coupling device G, and also as a winding path gear
when coupling device S_ab2 is disengaged, that a reverse gear R2 can be
shifted by means of the second clutch K2, the activated coupling device
C, the activated coupling device E and the activated coupling device H,
and also as a winding path gear when coupling device S_ab2 is disengaged,
a reverse gear R3 can be shifted by means of the second clutch K2, the
activated coupling device D, the activated coupling device E and the
activated coupling device H, and also as a winding path gear when
coupling device S_ab2 is disengaged, and/or a reverse gear R4 can be
shifted by means of the first clutch K1, the activated coupling device A,
the activated coupling device E and the activated coupling device G, and
also as a winding path gear when coupling device S_ab2 is disengaged.

[0072]Advantageously, in the 3rd variant embodiment the reverse gears R1,
R2 are power shiftable to the first forward gear (R1, R2 lsb. to G1).

[0073]Furthermore, in the 3rd variant embodiment a crawler gear C1 can be
shifted by means of the second clutch K2, the activated coupling device
C, the activated coupling device F and the activated coupling device H,
and also as a winding path gear when coupling device S_ab2 is disengaged,
a crawler gear C2 can be shifted by means of the first clutch K1 and the
activated coupling device A, and also as a winding path gear by means of
the activated shift element I, a crawler gear C3 can be shifted by means
of the first clutch K1 and the activated coupling device A, and also as a
winding path gear by means of the activated shift element K, and a
crawler gear C4 can be shifted by means of the first clutch K1, the
activated coupling device A, the activated coupling device F and the
activated coupling device G, and also as a winding path gear when
coupling device S_ab2 is disengaged.

[0074]Especially advantageously, the crawler gear C1 can be designed to be
power shiftable to the first forward gear (C1 lsb. to G1).

[0075]Finally, an overdrive gear O1 can also be shifted by means of the
second clutch K2 and the activated coupling device G, and also as a
winding path gear by means of the activated shift element I, an overdrive
gear O2 can be shifted by means of the second clutch K2 and the activated
coupling device H, and also as a winding path gear by means of the
activated shift element I, an overdrive gear O3 can be shifted by means
of the second clutch K2 and the activated coupling device H, and also as
a winding path gear by means of the activated shift element K, an
overdrive gear O4 can be shifted by means of the second clutch K2, the
activated coupling device B, the activated coupling device D and the
activated coupling device H, and also as a winding path gear when
coupling device S_ab1 is disengaged, and an overdrive gear O5 can be
shifted by means of the second clutch K2, the activated coupling device
B, the activated coupling device C and the activated coupling device H,
and also as a winding path gear when coupling device S_ab1 is disengaged.

[0076]The table depicted in FIG. 8 shows an example of a shift pattern for
the 4th variant embodiment of the eight-speed double clutch transmission
according to FIG. 7.

[0077]It is evident from the shift pattern that the first forward gear G1
is shiftable by means of the first clutch K1 and the activated coupling
device A, and also as a winding path gear by means of the activated shift
element I, that the second forward gear G2 is shiftable by means of the
second clutch K2 and the activated coupling device A, that the third
forward gear G3 is shiftable by means of the first clutch K1 and the
activated coupling device C, that the fourth forward gear G4 is shiftable
by means of the second clutch K2 and the activated coupling device B,
that the fifth forward gear G5 is shiftable by means of the first clutch
K1 and the activated coupling device G, that the sixth forward gear G6 is
shiftable by means of the second clutch K2 and the activated coupling
device F, and that the seventh forward gear G7 is shiftable by means of
the first clutch K1 and the activated coupling device D. Thus, at least
the first seven forward gears can be designed to be power shiftable.
Furthermore, the eighth forward gear G8 can be shifted by means of the
first clutch K1, the activated coupling device A, the activated coupling
device C and the activated coupling device F, and also as a winding path
gear when coupling device S_ab1 is disengaged.

[0078]Furthermore, in the 4th variant embodiment a reverse gear R1 can be
shifted by means of the second clutch K2, the activated coupling device
C, the activated coupling device E and the activated coupling device H,
and also as a winding path gear when coupling device S_ab2 is disengaged,
a reverse gear R2 can be shifted by means of the second clutch K2, the
activated coupling device D, the activated coupling device E, the
activated coupling device H, and also as a winding path gear when
coupling device S_ab2 is disengaged, and a reverse gear R3 can be shifted
by means of the second clutch K2, the activated coupling device C, the
activated coupling device F and the activated coupling device H, and also
as a winding path gear when coupling device S_ab2 is disengaged.

[0079]Further, a crawler gear C1 can also be shifted by means of the
second clutch K2, the activated coupling device A, the activated coupling
device D and the activated coupling device G, and also as a winding path
gear when coupling device S_ab1 is disengaged.

[0080]Finally, an overdrive gear O1 can also be shifted by means of the
second clutch K2 and the activated coupling device D, and also as a
winding path gear by means of the activated shift element I, an overdrive
gear O2 can be shifted by means of the second clutch K2 and the activated
coupling device D, and also as a winding path gear by means of the
activated shift element K, an overdrive gear O3 can be shifted by means
of the first clutch K1, the activated coupling device A, the activated
coupling device D and the activated coupling device F, and also as a
winding path gear when coupling device S_ab1 is disengaged, an overdrive
gear O4 can be shifted by means of the first clutch K1, the activated
coupling device B, the activated coupling device D and the activated
coupling device F, and also as a winding path gear when coupling device
S_ab1 is disengaged, and an overdrive gear O5 can be shifted by means of
the second clutch K2, the activated coupling device D, the activated
coupling device F and the activated coupling device G, and also as a
winding path gear when coupling device S_ab2 is disengaged.

[0081]The table depicted in FIG. 10 shows an example of a shift pattern
for the 5th variant embodiment of the eight-speed double clutch
transmission according to FIG. 9.

[0082]It is evident from the shift pattern that the first forward gear G1
is shiftable by means of the first clutch K1 and the activated coupling
device E, and also as a winding path gear by means of the activated shift
element I, that the second forward gear G2 is shiftable by means of the
second clutch K2 and the activated coupling device E, that the third
forward gear G3 is shiftable by means of the first clutch K1 and the
activated coupling device C, that the fourth forward gear G4 is shiftable
by means of the second clutch K2 and the activated coupling device B,
that the fifth forward gear G5 is shiftable by means of the first clutch
K1 and the activated coupling device H, that the sixth forward gear G6 is
shiftable by means of the second clutch K2 and the activated coupling
device F, that the seventh forward gear G7 is shiftable by means of the
first clutch K1 and the activated coupling device D, and that the eighth
forward gear G8 is shiftable by means of the second clutch K2, the
activated coupling device D, the activated coupling device E and the
activated coupling device G, and also as a winding path gear when
coupling device S_ab2 is disengaged. Thus, at least the first eight
forward gears can be designed to be power shiftable.

[0083]Furthermore, in the 5th variant embodiment a reverse gear R1 can be
shifted by means of the second clutch K2, the activated coupling device
A, the activated coupling device D and the activated coupling device G,
and also as a winding path gear when coupling device S_ab1 is disengaged,
a reverse gear R2 can be shifted by means of the first clutch K1 and the
activated coupling device A, and also as a winding path gear by means of
activated shift element K, a reverse gear R3 can be shifted by means of
the first clutch K1, the activated coupling device A, the activated
coupling device C and the activated coupling device E, and also as a
winding path gear when coupling device S_ab1 is disengaged, and a reverse
gear R4 can be shifted by means of the first clutch K1, the activated
coupling device A, the activated coupling device F and the activated
coupling device G, and also as a winding path gear when coupling device
S_ab2 is disengaged.

[0084]A crawler gear C1 can also be shifted by means of the second clutch
K2, the activated coupling device C, the activated coupling device E and
the activated coupling device H, and also as a winding path gear when
coupling device S_ab2 is disengaged.

[0085]Finally, an overdrive gear O1 can be shifted by means of the second
clutch K2 and the activated coupling device D, and also as a winding path
gear by means of the activated shift element I, an overdrive gear O2 can
be shifted by means of the second clutch K2, the activated coupling
device D, the activated coupling device F and the activated coupling
device H, and also as a winding path gear when coupling device S_ab2 is
disengaged, an overdrive gear O3 can be shifted by means of the first
clutch K1, the activated coupling device B, the activated coupling device
D and the activated coupling device F, and also as a winding path gear
when coupling device S_ab1 is disengaged.

[0086]The table depicted in FIG. 12 shows an example of a shift pattern
for the 6th variant embodiment of the eight-speed double clutch
transmission according to FIG. 11.

[0087]It is evident from the shift pattern that the first forward gear G1
is shiftable by means of the first clutch K1 and the activated coupling
device B, and also as a winding path gear by means of the activated shift
element K, that the second forward gear G2 is shiftable by means of the
second clutch K2 and the activated coupling device B, that the third
forward gear G3 is shiftable by means of the first clutch K1 and the
activated coupling device G, that the fourth forward gear G4 is shiftable
by means of the second clutch K2 and the activated coupling device F,
that the fifth forward gear G5 is shiftable by means of the first clutch
K1 and the activated coupling device D, that the sixth forward gear G6 is
shiftable by means of the second clutch K2 and the activated coupling
device E, and that the seventh forward gear G7 is shiftable by means of
the first clutch K1 and the activated coupling device C. Thus, at least
the first seven forward gears can be designed to be power shiftable.
Furthermore, the eighth forward gear G8 can be shifted by means of the
first clutch K1, the activated coupling device A, the activated coupling
device C and the activated coupling device F, and also as a winding path
gear when coupling device S_ab1 is disengaged.

[0088]Moreover, in the 6th variant embodiment a reverse gear R1 can be
shifted by means of the second clutch K2, the activated coupling device
D, the activated coupling device F and the activated coupling device H,
and also as a winding path gear when coupling device S_ab2 is disengaged.

[0089]Also, a crawler gear C1 can be shifted by means of the second clutch
K2 and the activated coupling device D, and also as a winding path gear
by means of the activated shift element I, a crawler gear C2 can be
shifted by means of the second clutch K2 and the activated coupling
device G, and also as a winding path gear by means of the activated shift
element I, a crawler gear C3 can be shifted by means of the second clutch
K2, the activated coupling device B, the activated coupling device D and
the activated coupling device G, and also as a winding path gear when
coupling device S_ab1 is disengaged, a crawler gear C4 can be shifted by
means of the first clutch K1, the activated coupling device B, the
activated coupling device E and the activated coupling device G, and also
as a winding path gear when coupling device S_ab2 is disengaged, and a
crawler gear C5 can be shifted by means of the second clutch K2, the
activated coupling device B, the activated coupling device C and the
activated coupling device G, and also as a winding path gear when
coupling device S_ab1 is disengaged.

[0090]Finally, an overdrive gear O1 can also be shifted by means of the
second clutch K2 and the activated coupling device C, and also as a
winding path gear by means of the activated shift element K, an overdrive
gear O2 can be shifted by means of the second clutch K2, the activated
coupling device C, the activated coupling device E and the activated
coupling device G, and also as a winding path gear when coupling device
S_ab2 is disengaged, an overdrive gear O3 can be shifted by means of the
second clutch K2, the activated coupling device D, the activated coupling
device E and the activated coupling device G, and also as a winding path
gear when coupling device S_ab2 is disengaged, an overdrive gear O4 can
be shifted by means of the first clutch K1 and the activated coupling
device E, and also as a winding path gear by means of the activated shift
element I, an overdrive gear O5 can be shifted by means of the first
clutch K1 and the activated coupling device F, and also as a winding path
gear by means of the activated shift element I, an overdrive gear O6 can
be shifted by means of the first clutch K1, the activated coupling device
B, the activated coupling device D and the activated coupling device E,
and also as a winding path gear when coupling device S_ab1 is disengaged,
an overdrive gear O7 can be shifted by means of the first clutch K1, the
activated coupling device B, the activated coupling device C and the
activated coupling device E, and also as a winding path gear when
coupling device S_ab1 is disengaged, and an overdrive gear O8 can be
shifted by means of the first clutch K1, the activated coupling device B,
the activated coupling device C and the activated coupling device F, and
also as a winding path gear when coupling device S_ab1 is disengaged.

[0091]The table depicted in FIG. 14 shows an example of a shift pattern
for the 7th variant embodiment of the eight-speed double clutch
transmission according to FIG. 13.

[0092]It is evident from the shift pattern that the first forward gear G1
is shiftable by means of the first clutch K1 and the activated coupling
device E, and also as a winding path gear by means of the activated shift
element K, that the second forward gear G2 is shiftable by means of the
second clutch K2 and the activated coupling device E, that the third
forward gear G3 is shiftable by means of the first clutch K1 and the
activated coupling device G, that the fourth forward gear G4 is shiftable
by means of the second clutch K2 and the activated coupling device F,
that the fifth forward gear G5 is shiftable by means of the first clutch
K1 and the activated coupling device D, that the sixth forward gear G6 is
shiftable by means of the second clutch K2 and the activated coupling
device A, that the seventh forward gear G7 is shiftable by means of the
first clutch K1 and the activated coupling device C, and that the eighth
forward gear G8 is shiftable by means of the second clutch K2, the
activated coupling device C, the activated coupling device E and the
activated coupling device H, and also as a winding path gear when
coupling device S_ab2 is disengaged. Thus, at least the first eight
forward gears can be designed to be power shiftable.

[0093]Furthermore, in the 7th variant embodiment a reverse gear R1 can be
shifted by means of the first clutch K1 and the activated coupling device
E, and also as a winding path gear by means of the activated shift
element I, a reverse gear R2 can be shifted by means of the first clutch
K1, the activated coupling device B, the activated coupling device D and
the activated coupling device E, and also as a winding path gear when
coupling device S_ab1 is disengaged, a reverse gear R3 can be shifted by
means of the first clutch K1, the activated coupling device B, the
activated coupling device D and the activated coupling device F, and also
as a winding path gear when coupling device S_ab1 is disengaged, and a
reverse gear R4 can be shifted by means of the first clutch K1, the
activated coupling device B, the activated coupling device C and the
activated coupling device E, and also as a winding path gear when
coupling device S_ab1 is disengaged.

[0094]Finally, an overdrive gear O1 can also be shifted by means of the
second clutch K2 and the activated coupling device C, and also as a
winding path gear by means of the activated shift element K.

[0095]The shift pattern according to FIG. 2 shows in detail that in the
first forward gear G1, starting from the first clutch K1 the gear stages
i_3, i_4 and i_2 are used, with the coupling of the two subtransmissions
occurring with coupling device S_ab1 disengaged. The second forward gear
G2 uses gear stage i_2, the third forward gear G3 uses gear stage the
fourth forward gear G4 uses gear stage i_4, the fifth forward gear G5
uses gear stage i_5, the sixth forward gear G6 uses gear stage i_6 and
the seventh forward gear G7 uses gear stage i_7. In the eighth forward
gear G8, starting from the second clutch K2 the gear stages or gear steps
i_6, ZW_8, and i_3 are used, with the two subtransmissions being coupled
in the first variant embodiment with coupling device S_ab2 disengaged.

[0096]In addition, in reverse gear R1, starting from the second clutch K2,
gear stages i_R, i_7 and ZW_8 are used, the two subtransmissions being
coupled to each other when coupling device S_ab1 is disengaged.
Furthermore, the next reverse gear R2, starting from the first clutch K1,
uses the gear stages i_3, i_R and i_2, the coupling device S_ab1 being
disengaged to couple the two subtransmissions. The reverse gear R3,
starting from the first clutch K1, uses the gear stages ZW_8, i_6 and
i_R, the two subtransmissions being coupled to each other when coupling
device S_ab2 is disengaged. The crawler gear C1, starting from the second
clutch K2, uses the gear stages i_4, i_7 and i_3, the two
subtransmissions being coupled with each other when shift element I is
activated. The crawler gear C2, starting from the second clutch K2, uses
the gear stages i_2, i_5 and i_3, the two subtransmissions being coupled
when coupling device S_ab2 is disengaged. The overdrive gear O1, starting
from the second clutch K2, uses the gear stages i_6, i_5 and i_7, the two
subtransmissions being coupled by means of the activated shift element K.
The overdrive gear O2, starting from the first clutch K1, uses the gear
stages i_7, i_4 and i_6, the two subtransmissions being coupled when
shift element I is activated. The overdrive gear O3, starting from the
second clutch K2, uses the gear stages i_6, i_5 and i_7, the two
subtransmissions being coupled when coupling device S_ab2 is disengaged.
The overdrive gear O4, starting from the first clutch K1, uses the gear
stages i_7, i_4 and i_6, the two subtransmissions being coupled when
coupling device S_ab1 is disengaged.

[0097]The shift pattern according to FIG. 4 shows in detail that in the
first forward gear G1, starting from the first clutch K1 the gear stages
i_3, i_4 and i_2 are used, with the coupling of the two subtransmissions
occurring when coupling device S_ab1 is disengaged. The second forward
gear G2 uses gear stage i_2, the third forward gear G3 uses gear stage
i_3, the fourth forward gear G4 uses gear stage i_4, the fifth forward
gear G5 uses gear stage i_5, the sixth forward gear G6 uses gear stage
i_6 and the seventh forward gear G7 uses gear stage i_7. In the eighth
forward gear G8, starting from the second clutch K2, the gear stages or
gear steps i_2, ZW_8, and i_7 are used, with the two subtransmissions
being coupled with coupling device S_ab2 disengaged in the first variant
embodiment.

[0098]In addition, in reverse gear R1, starting from the second clutch K2,
gear stages i_R, i_7 and ZW_8 are used, the two subtransmissions being
coupled to each other when coupling device S_ab1 is disengaged.
Furthermore, the next reverse gear R2, starting from the first clutch K1,
uses the gear stages i_3, i_R and i_2, the coupling device S_ab1 being
disengaged to couple the two subtransmissions. The reverse gear R3,
starting from the first clutch K1, uses the gear stages ZW_8, i_6 and
i_R, the two subtransmissions being coupled to each other when coupling
device S_ab2 is disengaged.

[0099]The crawler gear C1, starting from the second clutch K2, uses the
gear stages i_4, i_7 and i_3, the two subtransmissions being coupled with
each other when shift element I is activated. The crawler gear C2,
starting from the second clutch K2, uses the gear stages i_2, i_5 and
i_3, the two subtransmissions being coupled when coupling device S_ab2 is
disengaged. The overdrive gear O1, starting from the second clutch K2,
uses the gear stages i_6, i_5 and i_7, the two subtransmissions being
coupled by means of the activated shift element K. The overdrive gear O2,
starting from the first clutch K1, uses the gear stages i_7, i_4 and i_6,
the two subtransmissions being coupled when shift element I is activated.
The overdrive gear O3, starting from the second clutch K2, uses the gear
stages i_6, i_5 and i_7, the two subtransmissions being coupled when
coupling device S_ab2 is disengaged. The overdrive gear O4, starting from
the first clutch K1, uses the gear stages i_7, i_4 and i_6, the two
subtransmissions being coupled when coupling device S_ab1 is disengaged.

[0100]The shift pattern according to FIG. 6 shows in detail that the first
forward gear G1, starting from the first clutch K1, uses gear stage i_1.
The second forward gear G2 uses gear stage i_2, the third forward gear G3
uses gear stage i_3, the fourth forward gear G4 uses gear stage i_4, the
fifth forward gear G5 uses gear stage i_5, the sixth forward gear G6 uses
gear stage i_6 and the seventh forward gear G7 uses gear stage i_7. The
eighth forward gear G8, starting from the second clutch K2, uses the gear
stages i_2, i_1 and i_7, the coupling device S_ab1 being disengaged to
couple the two subtransmissions. In addition, the reverse gear R1,
starting from the second clutch K2, gear stages uses the gear stages,
i_R, i_5 and i_1, the two subtransmissions being coupled to each other
when coupling device S_ab2 is disengaged. The reverse gear R2, starting
from the second clutch K2, uses the gear stages i_R, i_7 and i_1, the two
subtransmissions being coupled to each other in reverse gear R2 when
coupling device S_ab2 is disengaged. The reverse gear R3, starting from
the second clutch K2, uses the gear stages i_R, i_7 and i_3, the two
subtransmissions being coupled with each other when coupling device S_ab2
is disengaged. The reverse gear R4, starting from the first clutch K1,
uses the gear stages i_5, i_R and i_2, the two subtransmissions being
coupled to each other when coupling device S_ab2 is disengaged.

[0101]Furthermore, the crawler gear C1, starting from the second clutch
K2, uses the gear stages i_6, i_7 and i_1, the subtransmissions being
coupled when coupling device S_ab2 is disengaged. The crawler gear C2,
starting from the first clutch K1, uses the gear stages i_1, i_4 and i_2,
the subtransmissions being coupled when shift element I is activated. The
crawler gear C3, starting from the first clutch K1, uses the gear stages
i_5, i_6 and i_2, the subtransmissions being coupled when shift element K
is activated. The crawler gear C4, starting from the first clutch K1,
uses the gear stages i_5, i_6 and i_3, the subtransmissions being coupled
when coupling device S_ab2 is disengaged. The overdrive gear O1, starting
from the second clutch K2, uses the gear stages i_4, i_1 and i_5, the two
subtransmissions being coupled to each other by means of the activated
shift element I. The overdrive gear O2, starting from the second clutch
K2, uses the gear stages i_4, i_1 and i_7, the two subtransmissions being
coupled to each other by means of the activated shift element I. The
overdrive gear O3, starting from the second clutch K2, uses the gear
stages i_6, i_5 and i_7, the two subtransmissions being coupled to each
other by means of the activated shift element K. The overdrive gear O4,
starting from the second clutch K2, uses the gear stages i_4, i_3 and
i_7, the two subtransmissions being coupled to each other when coupling
device S_ab1 is disengaged. The overdrive gear O5, starting from the
second clutch K2, uses the gear stages i_4, i_1 and i_7, the two
subtransmissions being coupled to each other when coupling device S_ab1
is disengaged.

[0102]The shift pattern according to FIG. 8 shows in detail that the first
forward gear G1, starting from the first clutch K1, uses the gear stages
i_3, i_4 and i_2, the two subtransmissions being coupled when shift
element I is activated. The second forward gear G2 uses gear stage i_2,
the third forward gear G3 uses gear stage i_3, the fourth forward gear G4
uses gear stage i_4, the fifth forward gear G5 uses gear stage i_5, the
sixth forward gear G6 uses gear stage i_6 and the seventh forward gear G7
uses gear stage i_7. The eighth forward gear G8, starting from the first
clutch K1, uses the gear stages i_3, i_2 and i_6, the two
subtransmissions being coupled when coupling device S_ab1 is disengaged.
In addition, the reverse gear R1, starting from the second clutch K2,
uses the gear stages _x5, i_R and i_3, the two subtransmissions being
coupled when coupling device S_ab2 is disengaged. The reverse gear R2,
starting from the second clutch K2, uses the gear stages _x5, i_R and
i_7, the two subtransmissions being coupled when coupling device S_ab2 is
disengaged. The reverse gear R3, starting from the second clutch K2, uses
the gear stages i_6, i_R and i_3, the two subtransmissions being coupled
when coupling device S_ab2 is disengaged.

[0103]The crawler gear C1, starting from the second clutch K2, uses the
gear stages i_2, i_7 and i_5, the two subtransmissions being coupled when
a coupling device S_ab1 is disengaged. In addition, the overdrive gear
O1, starting from the second clutch K2, uses the gear stages i_4, i_3 and
i_7, the two subtransmissions being coupled with each other by means of
the shift element I. The overdrive gear O2, starting from the second
clutch K2, uses the gear stages i_6, i_5 and i_7, the two
subtransmissions being coupled with each other by means of the shift
element K. The overdrive gear O3, starting from the first clutch K1, uses
the gear stages i_7, i_2 and i_6, the two subtransmissions being coupled
when coupling device S_ab1 is disengaged. The overdrive gear O4, starting
from the first clutch K1, uses the gear stages i_7, i_4 and i_6, the two
subtransmissions being coupled when a coupling device S_ab1 is
disengaged. The overdrive gear O5, starting from the second clutch K2,
uses the gear stages i_6, i_5 and i_7, the two subtransmissions being
coupled when a coupling device S_ab2 is disengaged.

[0104]The shift pattern according to FIG. 10 shows in detail that in the
first forward gear G1, starting from the first clutch K1, the gear stages
i_3, i_4 and i_2 are used, the subtransmissions being coupled by means of
the activated shift element I. The second forward gear G2 uses gear stage
i_2, the third forward gear G3 uses gear stage i_3, the fourth forward
gear G4 uses gear stage i_4, the fifth forward gear G5 uses gear stage
i_5, the sixth forward gear G6 uses gear stage i_6 and the seventh
forward gear G7 uses gear stage i_7. The eighth forward gear G8, starting
from the second clutch K2, uses the gear stages i_2, ZW_8 and i_7, the
subtransmissions being coupled when coupling device S_ab2 is disengaged.
In addition, the reverse gear R1, starting from the second clutch K2,
uses the gear stages i_R, i_7 and ZW_8, the subtransmissions being
coupled when coupling device S_ab1 is disengaged. The reverse gear R2,
starting from the first clutch K1, uses the gear stages ZW_8, i_6 and
i_R, the subtransmissions being coupled when shift element K is
activated. The reverse gear R3, starting from the first clutch K1, uses
the gear stages i_3, i_R and i_2, the subtransmissions being coupled when
coupling device S_ab1 is disengaged. The reverse gear R4, starting from
the first clutch K1, uses the gear stages ZW_8, i_6 and i_R, the
subtransmissions being coupled when coupling device S_ab2 is disengaged.

[0105]In addition, the crawler gear C1, starting from the second clutch
K2, uses the gear stages i_2, i_5 and i_3, the two subtransmissions being
coupled to each other when coupling device S_ab2 is disengaged. The
overdrive gear O1, starting from the second clutch K2, uses the gear
stages i_4, i_3 and i_7, the two subtransmissions being coupled to each
other by means of a shift element I. In addition, the overdrive gear O2,
starting from the second clutch K2, uses the gear stages i_6, i_5 and
i_7, the two subtransmissions being coupled to each other when coupling
device S_ab2 is disengaged. The overdrive gear O3, starting from the
first clutch K1, uses the gear stages i_7, i_4 and i_6, the two
subtransmissions being coupled when coupling device S_ab1 is disengaged.

[0106]The shift pattern according to FIG. 12 shows in detail that the
first forward gear G1, starting from the first clutch K1, uses the gear
stages i_3, i_4 and i_2, the two subtransmissions being coupled to each
other by means of the activated shift element K. The second forward gear
G2 uses gear stage i_2, the third forward gear G3 uses gear stage i_3,
the fourth forward gear G4 uses gear stage i_4, the fifth forward gear G5
uses gear stage i_5, the sixth forward gear G6 uses gear stage i_6 and
the seventh forward gear G7 uses gear stage i_7. The eighth forward gear
G8, starting from the first clutch K1, uses the gear stages i_7, ZW_8 and
i_4, the subtransmissions being coupled when coupling device S_ab1 is
disengaged. In addition, the reverse gear R1, starting from the second
clutch K2, uses the gear stages i_4, i_R and i_5, the subtransmissions
being coupled when coupling device S_ab2 is disengaged.

[0107]The crawler gear C1, starting from the second clutch K2, uses the
gear stages i_2, i_7 and i_5, the two subtransmissions being coupled with
each other when shift element I is activated. The crawler gear C2,
starting from the second clutch K2, uses the gear stages i_2, i_7 and
i_3, the two subtransmissions being coupled to each other when shift
element I is activated. The crawler gear C3, starting from the second
clutch K2, uses the gear stages i_2, i_5 and i_3, the two
subtransmissions being coupled to each other when coupling device S_ab1
is disengaged. The crawler gear C4, starting from the first clutch K1,
uses the gear stages i_3, i_6 and i_2, the two subtransmissions being
coupled to each other when coupling device S_ab2 is disengaged. The
crawler gear C5, starting from the second clutch K2, uses the gear stages
i_2, i_7 and i_3, the two subtransmissions being coupled to each other
when coupling device S_ab1 is disengaged.

[0108]The overdrive gear O1, starting from the second clutch K2, uses the
gear stages i_4, i_3 and i_7, the two subtransmissions being coupled to
each other when shift element K is activated. In addition, the overdrive
gear O2, starting from the second clutch K2, uses the gear stages i_6,
i_3 and i_7, the two subtransmissions being coupled to each other when
coupling device S_ab2 is disengaged. In addition, the overdrive gear O3,
starting from the second clutch K2, uses the gear stages i_6, i_3 and
i_5, the subtransmissions being coupled to each other when coupling
device S_ab2 is disengaged. The overdrive gear O4, starting from the
first clutch K1, uses the gear stages i_7, i_2 and 1_6, the
subtransmissions being coupled with each other when shift element I is
activated. The overdrive gear O5, starting from the first clutch K1, uses
the gear stages i_7, i_2 and i_4, the subtransmissions being coupled to
each other when shift element I is activated. The overdrive gear O6,
starting from the first clutch K1, uses the gear stages i_5, i_2 and i_6,
the subtransmissions being coupled to each other when coupling device
S_ab1 is disengaged. The overdrive gear O7, starting from the first
clutch K1, uses the gear stages i_7, i_2 and i_6, the subtransmissions
being coupled to each other when coupling device S_ab1 is disengaged. The
overdrive gear O8, starting from the first clutch K1, uses the gear
stages i_7, i_2 and i_4, the subtransmissions being coupled to each other
when coupling device S_ab1 is disengaged.

[0109]The shift pattern according to FIG. 14 shows in detail that the
first forward gear C1, starting from the first clutch K1, uses the gear
stages i_3, i_4 and i_2, the two subtransmissions being coupled to each
other by means of the activated shift element K. The second forward gear
G2 uses gear stage i_2, the third forward gear G3 uses gear stage i_3,
the fourth forward gear G4 uses gear stage i_4, the fifth forward gear G5
uses gear stage i_5, the sixth forward gear G6 uses gear stage i_6 and
the seventh forward gear G7 uses gear stage i_7. The eighth forward gear
G8, starting from the second clutch K2, uses the gear stages i_2, ZW_8
and i_7, the two subtransmissions being coupled to each other when
coupling device S_ab2 is disengaged. In addition, the reverse gear R1,
starting from the first clutch K1, uses the gear stages i_7, i_R and i_2,
the subtransmissions being coupled when shift element I is activated. The
next reverse gear R2, starting from the first clutch K1, uses the gear
stages i_5, i_R and i_2, the subtransmissions being coupled when coupling
device S_ab1 is disengaged. The reverse gear R3, starting from the first
clutch K1, uses the gear stages i_5, i_R and i_4, the subtransmissions
being coupled when coupling device S_ab1 is disengaged. The reverse gear
R4, starting from the first clutch K1, uses the gear stages i_7, i_R and
i_2, the subtransmissions being coupled when coupling device S_ab1 is
disengaged.

[0110]The overdrive gear O1, starting from the second clutch K2, uses the
gear stages i_4, i_3 and i_7, the two subtransmissions being coupled to
each other when shift element K is activated.

[0111]In summary, the result for the 1st, 2nd and 3rd variant embodiments
according to FIGS. 1 through 6, with the winding path gear coupling
devices S_ab1 and S_ab2, without other winding path gear shift elements,
is that three dual gear planes and two single gear planes are provided.

[0112]In the 1st variant embodiment, the first forward gear G1 and the
eighth forward gear G8 can be designed as winding path gears. In
addition, a reverse gear R2 that is power shiftable to the second forward
gear is provided, thereby enabling rocking free when stuck. Furthermore,
an additional overdrive gear O3 that is power shiftable to the seventh
forward gear is realizable as an alternative power shiftable eighth
forward gear, to save fuel.

[0113]In detailed terms, the result for the 1st variant embodiment is that
in the first gear plane 8-12, as a dual gear plane, idler gear 8 is used
for three forward gears, R1, R2, R3, and idler gear 12 for three forward
gears G1, G2, C2 and for one reverse gear R2. In the second gear plane
9-2, as a single gear plane, idler gear 9 is used for five forward gears
G1, G4, C1, O2, O4. In the third gear plane 3-13, as a single gear plane,
idler gear 13 is used for six forward gears G6, G8, O1, O2, O3, O4 and
for one reverse gear R3. In the fourth gear plane 10-14, as a dual gear
plane, idler gear 10 is used for six forward gears G7, C1, O1, O2, O3, O4
and for one reverse gear R1, and idler gear 14 for four forward gears G5,
C2, O1, O3. In the fifth gear plane 11-15, as a dual gear plane, idler
gear 11 is used for five forward gears G1, G3, G8, C1, C2 and for one
reverse gear R2, and idler gear 15 for one forward gear G8 and for two
reverse gears R1, R3.

[0114]In summary, the 2nd variant embodiment according to FIGS. 3 and 4
results in the same advantages as the 1st variant embodiment, but with
the additional advantage that that the eighth forward gear can be
designed as a power shiftable winding path gear.

[0115]In detailed terms, the result for the 2nd variant embodiment is that
in the first gear plane 8-12, as a dual gear plane, idler gear 8 is used
for three forward gears, R1, R2, R3, and idler gear 12 for four forward
gears G1, G2, G8, C2 and for one reverse gear R2. In the second gear
plane 9-2, as a single gear plane, idler gear 9 is used for five forward
gears G1, G4, O1, O2, O4. In the third gear plane 3-13, as a single gear
plane, idler gear 13 is used for five forward gears G6, O1, O2, O3, O4
and for one reverse gear R3. In the fourth gear plane 10-14, as a dual
gear plane, idler gear 10 is used for seven forward gears G7, G8, C1, O1,
O2, O3, O4 and for one reverse gear R1, and idler gear 14 for four
forward gears G5, C2, O1, O3. In the fifth gear plane 11-15, as a dual
gear plane, idler gear 11 is used for four forward gears G1, G3, C1, C2
and for one reverse gear R2, and idler gear 15 for one forward gear G8
and for two reverse gears R1, R3.

[0116]In the 3rd variant embodiment, the first forward gear is not a
winding path gear, but the eighth forward gear can be designed as a power
shiftable winding path gear. In addition, two reverse gears R1, R2 that
are power shiftable to the first forward gear are realizable, enabling
rocking free when stuck. Another result is a crawler gear C1 that is
power shiftable to the first forward gear, to enable better off-road
driving properties. Finally, two additional overdrive gears O4, O5 that
are power shiftable to the seventh forward gear can be made possible as
alternative power shiftable eighth forward gears, to save fuel.

[0117]In detailed terms, the result for the 3rd variant embodiment is that
in the first gear plane 8-12, as a dual gear plane, idler gear 8 is used
for four forward gears G1, G8, C2, C3 and for one reverse gear R4, and
idler gear 12 for four reverse gears R1, R2, R3, R4. In the second gear
plane 9-2, as a single gear plane, idler gear 9 is used for six forward
gears G4, C2, O1, O2, O4, O5. In the third gear plane 3-13, as a single
gear plane, idler gear 13 is used for five forward gears G6, C1, C3, C4,
O3. In the fourth gear plane 10-14, as a dual gear plane, idler gear 10
is used for seven forward gears G1, G8, C1, C2, O1, O2, O5 and for two
reverse gears R1, R2, and idler gear 14 for five forward gears G5, C3,
C4, O1, O3 and for two reverse gears R1, R4. In the fifth gear plane
11-15, as a dual gear plane, idler gear 11 is used for three forward
gears G3, C4, O4 and for one reverse gear R3, and idler gear 15 for seven
forward gears G7, G8, C1, O2, O3, O4, O5 and for two reverse gears R2,
R3.

[0118]In summary, the result for the 4th and 5th variant embodiments
according to FIGS. 7-10, with the two winding path gear coupling devices
S_ab1 and S_ab2 and with the additional winding path gear shift element
I, is that the first and the eighth forward gears are shiftable as
winding path gears.

[0119]In the 4th variant embodiment according to FIGS. 7 and 8, two dual
gear planes and three single gear planes are provided. Furthermore, two
additional overdrive gears O1, O5 that are power shiftable to the seventh
forward gear are realizable as alternative power shiftable eighth forward
gears, to save fuel.

[0120]In detailed terms, the result for the 4th variant embodiment is that
in the first gear plane 8-1, as a single gear plane, idler gear 8 is used
for five forward gears G1, G2, G8, C1, O3. In the second gear plane 9-2,
as a single gear plane, idler gear 9 is used for four forward gears G1,
G4, O1, O4. In the third gear plane 3-13, as a single gear plane,
idler gear 13 is used for six forward gears G6, G8, O2, O3, O4, O5 and
for one reverse gear R3. In the fourth gear plane 10-14, as a dual gear
plane, idler gear 10 is used for four forward gears G1, G3, G8, O1 and
for two reverse gears R1, R3, and idler gear 14 for four forward gears
G5, C1, O2, O5. In the fifth gear plane 11-15, as a dual gear plane,
idler gear 11 is used for seven forward gears G7, C1, O1, O2, O3, O4, O5
and for one reverse gear R2, and idler gear 10 for three reverse gears
R1, R2, R3.

[0121]In summary, the result for the 5th variant embodiment according to
FIGS. 9 and 10, with three dual gear planes and two single gear planes,
is a power-shiftable eighth forward gear as a winding path gear. Another
result is a reverse gear R3 that is power shiftable to the second forward
gear, thereby enabling rocking free when stuck. A further result is two
additional overdrive gears O1, O2 that are power shiftable to the seventh
forward gear, as alternative power-shiftable eighth forward gears to save
fuel.

[0122]In detailed terms, the result for the 5th variant embodiment is that
in the first gear plane 8-12, as a dual gear plane, idler gear 8 is used
for four reverse gears, R1, R2, R3, R4, and idler gear 12 for four
forward gears G1, G2, G8, C1 and for one reverse gear R3. In the second
gear plane 9-2 idler gear 9 is used for four forward gears G1, G4, O1,
O3. In the third gear plane 3-13, as a single gear plane, idler gear 13
is used for three forward gears G6, O2, O3 and for two reverse gears R2,
R4. In the fourth gear plane 10-14, as a dual gear plane, idler gear 10
is used for four forward gears G1, G3, C1, O1 and for one reverse gear
R3, and idler gear 14 for one forward gear G8 and for three reverse gears
R1, R2, R4. In the fifth gear plane 11-15, as a dual gear plane, idler
gear 11 is used for five forward gears G7, G8, O1, O2, O3 and for reverse
gear R1, and idler gear 15 for three forward gears G5, C1, O2.

[0123]In summary, the result for the 6th and 7th variant embodiments, with
the two winding path gear coupling devices S_ab1 and S_ab2 and the
winding path gear shift element K, is the first forward gear and the
eighth forward gear as winding path gears, with three dual gear planes
and two single gear planes being provided.

[0124]A further result in the 6th variant embodiment is that the eighth
forward gear is not power shiftable. In addition, a crawler gear C4 that
is power shiftable to the second forward gear may be realized for better
off-road driving properties. A further result is two additional overdrive
gears O1, O2 that are power shiftable to the seventh forward gear, as
alternative power-shiftable eighth forward gears to save fuel.

[0125]In detailed terms, the result for the 6th variant embodiment is that
in the first gear plane 8-12, as a dual gear plane, idler gear 8 is used
for one forward gear G8, and idler gear 12 for seven forward gears G6,
C4, O2, O3, O4, O6, O7. In the second gear plane 9-13, as a dual gear
plane, idler gear 9 is used for 12 forward gears G1, G2, C1, C2, C3, C4,
C5, O4, O5, O6, O7, O8, and idler gear 13 for six forward gears G1, G4,
G8, O1, O5, O8 and for one reverse gear R1. In the third gear plane 10-3,
as a single gear plane, idler gear 10 is used for 11 forward gears G7,
G8, C1, C2, C5, O1, O2, O4, O5, O7, O8. In the fourth gear plane 4-14, as
a single gear plane, idler gear 14 is used for nine forward gears G1, G3,
C2, C3, C4, C5, O1, O2, O3. In the fifth gear plane 11-15, as a dual gear
plane, idler gear 11 is used for five forward gears G5, C1, C3, O3, O6
and for one reverse gear, and idler gear 15 for one reverse gear R1.

[0126]A further result in the 7th variant embodiment is that the eighth
forward gear can be designed to be power shiftable. Another result is two
reverse gears R2, R4 that are power shiftable to the second forward gear,
thereby enabling rocking free when stuck. Furthermore, an additional
overdrive gear O1 that is power shiftable to the seventh forward gear can
be realized as an alternative power-shiftable eighth forward gear, to
save fuel.

[0127]In detailed terms, the result for the 7th variant embodiment is that
in the first gear plane 8-12, as a dual gear plane, idler gear 8 is used
for one forward gear G6, and idler gear 12 for three forward gears G1,
G2, G8 and for three reverse gears R1, R2, R4. In the second gear plane
9-13, as a dual gear plane, idler gear 9 is used for four reverse gears
R1, R2, R3, R4, and idler gear 13 for four forward gears G1, G4, O1 and
for one reverse gear R3. In the third gear plane 10-3, as a single gear
plane, idler gear 10 is used for three forward gears G7, G8, O1 and for
two reverse gears R1, R4. In the fourth gear plane 4-14, as a single gear
plane, idler gear 14 is used for three forward gears G1, G3, O1. In the
fifth gear plane 11-15, as a dual gear plane, idler gear 11 is used for
one forward gear G5 and for two reverse gears R2, R3, and idler gear 15
for one forward gear G8.

[0128]It is possible that in one or more variant embodiments at least one
additional gear stage ZW_x (e.g., ZW_8) may be utilized for winding path
gears that are not used in a direct forward gear. The utilization of an
additional gear stage is evident from the figures for the respective
variant embodiments.

[0129]It is also possible to use gear wheels x1, x2, . . . x7, x8 for
additional winding path gears, which may be added to supplement a single
gear plane, the gear wheels x1, x2, . . . x7, x8 being numbered as
follows. The numbering begins with the first gear wheel x1 of the first
countershaft w_v1, starting from the assigned output stage i_ab_1 and
continuing sequentially until the fourth gear wheel x4, the first gear
wheel on the second countershaft w_v2 starting from the assigned output
stage i_ab_2 being designated as x5 and the additional gear wheels being
designated continuously up to x8. If the additional gear wheel x1, x2, .
. . x7, x8 is used in a reverse gear transmission, a rotation reversal
will take place, as for example through the use of an intermediate gear
ZR on an intermediate shaft w_zw or the like.

[0130]In all variant embodiments of the double clutch transmission,
because of these provisions for multiple use of individual idler gears,
fewer gear planes are necessary, and thus fewer parts while the number of
gears remains the same, so that an advantageous saving of construction
space and cost is achieved.

[0131]Independent of the particular variant embodiment, the number "1" in
a field of the particular table of the shift patterns according to FIGS.
2, 4, 6, 8, 10, 12 and 14 means that the assigned clutch K1, K2 or the
assigned coupling device A, B, C, D, E, F, G, H or the assigned shift
element I, K is engaged or activated. On the other hand, a blank field in
the particular table of the shift patterns according to FIGS. 2, 4, 6, 8,
10, 12 and 14 means that the assigned clutch K1, K2 or the assigned
coupling device A, B, C, D, E, F, G, H or the assigned shift element I, K
is disengaged.

[0132]For the coupling device S_ab1 or S_ab2 assigned to an output gear 17
or 18, deviating from the previously stated rules, when there is a blank
field in the respective table of the shift patterns according to FIGS. 2,
4, 6, 8, 10, 12 and 14 the coupling device S_ab1 or S_ab2 must be
disengaged, and when there is a field with the number "1" in the
respective table of the shift patterns according to FIGS. 2, 4, 6, 8 ,10,
12 and 14 the coupling device S_ab1 or S_ab2 should be engaged. Depending
on the gear, the coupling element S_ab1 or S_ab2 must be engaged even in
the case of a group of gears where there is a field with the number "1,"
whereas in contrast, for a different group of gears where there is a
field with the number "1," the coupling element S_ab1 or S_ab2 may be
either disengaged or engaged.

[0133]Furthermore, in many cases the possibility exists of inserting
additional coupling or shift elements without influencing the flow of
force. This can enable gear preselection.